If you could go back in time and see three different things that happened what would they be?

Verbi Gratia:
1. The Beatles playing a concert.
2. The signing of The Declaration of Independence.
3. The Sphinx in it's prime.

Rules: (because most things like this have them.)
1. You are merely a spectator, therefore you can not interact with anything/one.
2. You may not bring anything with you, there or back.
3. It can be any point in time that has already come and passed. (And no saying "Time is an illusion")